On Friday, shells were hitting the districts of Baba Amr, Inshaat, Bayada and Khaldiya, opposition and human rights activist said.

"The shelling is continuous. They are using rockets and mortars, which are falling on people's houses," Homs resident Abu Abdah told the BBC. "The damage is so huge, and the city has been isolated."

"We have no support. We have a lack of medical supplies and food. The Assad forces have prevented people leaving the city."

At least five people were killed in Friday's attacks, The Associated Press reports, citing activists in the city.

According to the AP:

Activist groups said tens of thousands of protesters poured into the streets after Friday prayers from Daraa in the south to Aleppo and Idlib in the north and Deir el-Zour in the east to areas around the capital Damascus. The Local Coordination Committees said security forces opened fire on some protests.

Syrian troops have attacked Homs for two weeks, trying to rout hundreds of rebel fighters in the city. The United Nations says 5,400 people have been killed since a crackdown on activists began nearly a year ago.

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